Method for controlling flux of electromagnet and an electromagnet for carrying out sad method (variants)

ABSTRACT

The group of inventions relates to magnetic systems, in particular to a method for controlling the flux of electromagnet and to the structural design of an electromagnet which is used for carrying out said method. The inventive structures of the electromagnet can be mainly used for electromechanical actuating devices and comprise a magnetic coil provided with a composite magnetic core made at least partially of hard-magnetic material and provided at least with one air gap. The novelty of the invention lies in that the composite magnetic core is embodied in such a way that it has at least two stable magnetic states, said magnetic core has each said state (the air gap being minimized) as a result of the action of the control current pulses supplied to the magnetic coil winding and having different (opposite) polarities, respectively. The specified values of the magnetic flux correspond to the stable states of the magnetic core of the electromagnet when in it is devoid of electric current in the magnetic coil winding thereof. Said invention makes it possible to substantially increase the efficiency of electromagnet by increasing the attractive and holding forces thereof, improving the mass and dimensional characteristics and the operational safety thereof, and also by energy saving and extending the functional capabilities of said structural design of the inventive electromagnet which uses the inventive method for controlling the magnetic flux.

The group of inventions relates to magnetic systems, and in particularto a method of controlling a magnetic flux of an electromagnet as wellas to constructions of the electromagnet carrying out said method.

The proposed group of inventions can be used preferably in executingdevices of electromechanical field, in particular in magnetic starters,contactors and vacuum switches, locking devices for blocking locks ofsafe boxes, automobiles, doors, and the like devices for the purpose ofpreventing unauthorized penetration, and also in overrunning couplings,connecting couplings, braking mechanisms and other constructions.

In said constructions an electromagnet which performs the function of anelectromechanical drive includes a magnetizing coil on a magnetic guideof ferromagnetic material, at least with one air gap. When voltage issupplied to a winding of the magnetizing coil of ferromagnetic materialof the magnetic guide, a magnetic flux which is excited in the magneticguide attracts a movable core. When the voltage is removed from thewinding of the magnetizing coil, the magnetic flux disappears, and as aresult of it a force which attracts the core disappears, and under theaction of a return spring the core returns to its initial position.

A method is known for controlling a magnetic flux of an electromagneticwith a relay pulling characteristic which is determined by stable levelsof values of a magnetic flux in a magnetic guide, composed at leastpartially of a magnetically hard material and with at least one air gap,by supplying controlling pulses of electric current into a winding ofthe magnetizing coil with a possibility of obtaining an attracting forceof a movable part of the magnetic guide-a core of the electromagnet, seefor example DE 19639545 A1 of Dec. 18, 1997, applicant ICON, AGPRAZISIONSTECINIC (1).

The known method is not sufficiently efficient. This is connected withthe fact that during controlling of the magnetic flux in the magneticguide, in accordance with the method, a closing of a magnetic circuit ofthe magnetic guide of the electromagnet is not provided, and a fixationof its movable part—a core in extreme positions is carried out in amechanical way, or in other words with the use of mechanical means, andin particular by means of the use of balls which are spring-biased by aring and enter corresponding ring grooves in end positions of themovable part of the magnetic guide of the electromagnet. The result ofthis is a relatively insufficient exploitation reliability due toincreased mechanical wear, which contributes to an increase ofprobability of failures in the operation and reduction of service lifebefore failure, limits the value of pulling and attracting force.

Moreover, the known method does not guarantee a minimization of the airgap and correspondingly, closing of the magnetic circuit of the magneticguide.

The closest, in accordance with a technical substance and the achievedresult, to the claimed method is a method of controlling a magnetic fluxof an electromagnet with a relay pulling characteristic, determined bystable levels of values of a magnetic flux in a magnetic guide, formedat least partially of a magnetically hard material and with at least oneair gap, by means of supply of controlling pulses of electrical currentin a winding of a magnetizing coil with a possibility of obtaining anattracting force of a movable part of a magnetic guide-core ofelectromagnet, see for example European patent EP 0794540 A1 of Sep. 10,1997, applicant HARTING KGaA CNJK, TW 2 CNIJRB, prototype (2).

In the known method for controlling a magnetic flux of an electromagnet,partially the above mentioned disadvantages are eliminated, because itprovides a higher exploitation reliability. However, the efficiency ofthe known method continues to remain relatively insufficient due to arelatively insufficient functional possibilities of the electromagnet.This is connected with the fact that the known method also does notprovide a closing of a magnetic circuit of the magnetic guide of theelectromagnet due to a constant presence of an air gap in a magneticcircuit of the electromagnet. Moreover, the known method can not providea possibility of remagnetization, demagnetization of the magneticallyhard material of the magnetic guide or another action on it in the caseof changing of the magnetic flux in the magnetic guide, created by amagnetizing coil.

An electromagnet of an actuating device is known, preferably of amagnetic drive, which is formed as at least one magnetizing coil on acomposite magnetic guide with an immovable stator, a movable core and atleast one air gap, wherein at least a part of the magnetic guide isformed as an insert of a magnetically hard material with a possibilityof controlling a magnetic flux in the magnetic guide by itsremagnetization by supply of short-term pulses of current of differentpolarity into a winding of the magnetizing coil, see for example DE19639545 A1 of Dec. 18, 1997, applicant ICON, AG PRAZISIONSTECINIC (3).

The known electromagnet does not provide a closed metallic construction,and thereby its sufficiency is reduced due to sufficiently high magneticdispersing fluxes and also due to significant losses of a magneticenergy in the air gap. Moreover, the construction of the knownelectromagnet does not have a property of “magnetic memory” (here andlater on the term “magnetic memory” is used for explanation of anability of a composite magnetic guide to accumulate a magnetic energy atthe level of a magnetic flux, created by a magnetizing coil).

Also known is an electromagnet of an electromagnetic drive of anactuating device, preferably a magnetic drive, which is formed as atleast one magnetizing coil on a composite magnetic guide with animmovable stator, a movable core and at least one air gap, wherein atleast a part of the magnetic guide is formed as an insert of amagnetically hard material with a possibility of controlling a magneticflux in the magnetic guide by its remagnetization due to the supply ofshort term pulses of current of different polarities into a winding ofthe magnetizing coil, see for example European patent EP 0794540 A1 ofSep. 10, 1997, applicant HARTING, KGaA CNJK, TW 2 CNIJGRB (4).

In the known construction of this electromagnet a part of the core iscomposed of a magnetically hard material. However, this compositemagnetic guide of the known electromagnet does not provide a closedcircuit of the magnetic guide due to the presence of a sliding bearingbetween the core and a cover, and also the presence because of this of apermanent air gap in the magnetic guide. In addition, the efficiency ofthe known electromagnet is insufficient because the insert of permanentmagnet used in its magnetic guide is located with a strict orientationof its magnetic poles, and in particular “S” and “N”, which causes“adherence” of the core to a place on a bottom of the cylinder. Becauseof this, and also because of the presence, in addition to this, of aparallel branch of the magnetic guide of a magnetically soft materialwhich passes through the middle of the permanent magnet—a magneticinsert of a ring shape, the magnetically hard material of its magneticguide does not remagnetize, or in other words it is not demagnetized,and as a result of this it therefore is not subjected to any controllingaction on the magnetically hard material from the side of themagnetizing coil, since the magnetic flux created by the magnetizingcoil passes in the magnetic guide along a path of the least magneticresistance, and in particular along a path of the maximum magneticconductivity in a parallel branch of the magnetically soft material. Asa result of this, the magnetic guide of the known electromagnet does nothave the property of “zeroing ” of the magnetic flux in the magneticguide (here and later the term “zeroing” is used for the cases when themagnetic flux is equal to zero, or for the cases φ=0). In other words,when the current pulse in the winding of the magnetizing coil is absent,the value of the magnetic flux in the composite magnetic guide of theknown electromagnet is not sufficient for providing a necessary force ofattraction of the movable core, since the force of attraction in theknown electromagnet corresponds to a force created by a simple bipolarpermanent magnet. A release of the core from the bottom, or in otherwords a return of the core, is provided by creating with a magnetizingcoil of a magnetic flux with a reverse, or in other words opposite,direction, which compensates the magnetic flux constantly created by themagnetically hard insert. Therefore the known electromagnet has suchdisadvantages as a relatively weak holding force, an insufficientreliability during exploitation, and an insufficient functionality.

The closest, in accordance with a technical substance and an achievedresult, to the claimed device is a known electromagnet of anelectromagnetic device of an executing device preferably a magneticdrive, which is formed as at least one magnetizing coil on a compositemagnetic guide with an immovable stator, a movable core and at least oneair gap, wherein at least a part of the magnetic guide is formed as aninsert of a magnetically hard material with a possibility of controllinga magnetic flux in the magnetic guide by its remagnetization due to thesupply of short time current pulses of different polarity into thewinding of the magnetizing coil, see for example international patentapplication PCT/UA00/0005 H01F 7/16, 7/124 E05 B 47/02, of Feb. 3, 2000,applicant BABICH, N. S.-prototype (5).

In this construction the above mentioned disadvantages are partiallyeliminated. However, its efficiency is insufficient since the insert ofthe magnetically hard material is located on a movable part of themagnetic guide, or in other words on the core. Because of this, duringthe displacement of the core with the insert of the magnetically hardmaterial relative to the convolutions of the winding of the magnetizingcoil it induces an electrodynamic force of a mutual induction in thewinding, which creates in the magnetic guide of the electromagnet amagnetic flux directed toward the main flux or in other words to thecontrolling flux generated by the same winding. In this case the vectorsof said fluxes have practically equal magnitudes, though they areshifted in phase. Due to this, the resulting magnetical moving force(later in the text MMF) and an attracting force created by the magneticinsert is reduced. Therefore, the exploitation efficiency of the knownconstruction of the electromagnet is practically not high. Moreover, adisadvantage of the known construction is that said MMF of mutualinduction does not give a possibility to provide a frequency ofswitching off of the magnetic system of the electromagnet, since withswitching off and return of the core to an initial position, the insertof the magnetically hard material moves relative to the convolutions ofthe currentless magnetizing coil, induces electric current in thewinding of the coil and is magnetized itself, or in other words is notcompletely “zeroed”, which can cause an unauthorized attraction of thecore.

The basis of this invetion is an objective to increase exploitationefficiency by means of reducing of energy consumption, by means ofincreasing of a reliability due to reduction of a number of failures andincrease service life before failure, by means of improving of mass-sizeparameters, and also by means of increase of functionality of theelectromagnet or in other words expansion of its functionalpossibilities.

This objective is solved in the invention in that, in the known methodof controlling a magnetic flux of an electromagnet with a relay pullingcharacteristic, determined by stable levels of values of a magnetic fluxin a composite magnetic guide, which at least partially is composed of amagnetically hard material and at least partially has one air gap, bymeans of supply of controlling pulses of electric current into a windingof a magnetizing coil with a possibility of obtaining an attractiveforce of a movable part of a magnetic guide of the electromagnet, inaccordance with the present invention, a magnetically hard material isused which has a property to maintain at least two stable conditions ofmagnetization, and as controlling pulses of electric current, in themagnetizing winding of a composite magnetic guide of the electromagnetat least two short term pulses are supplied, wherein during the supplyof a first pulse a closing of the magnetic circuit of the magnetic guideis provided and a minimization of its magnetic resistance due tominimization of air gap of the magnetic guide with a subsequentmaximization of the magnetic flux in the magnetic guide and itstransition to one of the stable conditions, characterized by a maximalvalue of the magnetic flux in the magnetic guide, which corresponds toan energy of controlling pulse action, with a possibility of staying ofthe composed magnetic guide of the electromagnet in this stablecondition and by providing of its holding force until a supply ofanother controlling pulse of electric current, whose energycharacteristic in its magnitude is sufficient for transfer of themagnetic guide into another stable condition which is characterized byanother magnitude of the magnetic flux corresponding to it, and anothermagnitude of a holding force corresponding to it.

The set objective is also solved in that the supply of the firstcontrolling pulse of current into the winding of the magnetizing coilwith a subsequent maximization of the magnetic flux in the compositemagnetic guide is performed till minimization of the air gap, and alsoin that said supply of the first controlling parts of current into thewinding of the magnetizing coil with subsequent maximization of themagnetic flux in the composite magnetic guide is performed after theminimization of the air gap.

The set objective in the invention is also solved in that the magnitudeof the controlling magnetic flux in the composite magnetic guide of theelectromagnet due to the first controlling pulse of electric current inthe winding of the magnetizing of the electromagnet until closing of themagnetic circuit of the magnetic guide is provided at a level of itsoptimal value, which is necessary for generating an attracting force ofthe electromagnet, and it is maintained at a level til elimination of anair gap and magnetization of the material of the magnetic guid, andthereafter the electric pulse voltage is removed from the winding of themagnetizing coil, and the holding force of the electromagnet is provideddue to a “magnetic memory” of the material of the composite magneticguide with a possibility of obtaining a holding force, whose value isF≦0.98 F_(max) wherein F_(max)—is a maximal value of the magnetic flux,generated by the winding of the magnetizing coil.

The set objective is also solved in that the required power of thecontrolling pulses with the possibility of providing a necessary forceof the electromagnet is provided due to changing of parameters ofcontrolling pulses, selected from a row composed of an amplitude of apulse, its duration, its shape, their combinations.

Moreover, the objective of the invention is solved in that into thewinding of the magnetizing coil a second controlling current pulse issupplied with a different energy characteristic when compared with acharacteristic of the first controlling pulse, and a transfer of themagnetic guide is provided into one of other stable conditions—a thirdstable condition which is characterized by a corresponding magnitude ofthe magnetic flux in the composite magnetic guide and the correspondingmagnitude of the holding force.

The objective is also in that a transfer of the magnetic guide isprovided into a stable position which is characterized by a magnitude ofthe magnetic flux in the magnetic guide equal to zero, by supplying inthe winding of the magnetizing coil a controlling current pulse whichprovides an intensity of the magnetic field in the magnetic guide, equalto coercitive force on a magnetizing curve and a corresponding magnitudeof a holding force. During this process one of a stabile conditions ofthe composite magnetic guide is its initial condition which ischaracterized by a magnetic flux whose magnitude is equal to an initialvalue, and a value of a holding force which corresponds to it.

In this process the objective is also solved in that a power P₂ of thesecond controlling current pulse of an opposite polarity is provided 2:5times less than the power of polarity P₁ of the first controlling pulseof a direct polarity and corresponds to P₁=(2÷5) P₂.

A duration t₁ of the first controlling pules of electric current of thedirect polarity and correspondingly t₂ of the second controlling pulseof opposite polarity in the winding of the magnetizing coil and,correspondingly, a duration of pulses of the magnetic flux in thecomposite magnetic guide of the electromagnet is provided with such amagnitude which does not exceed the magnitude of the triple constant oftime τ of the transitional process for a mass of the movable part of themagnetic guide or in other words t₁≦3 τ and t₂≦3 τ, wherein τ is a timeconstant of the transitional process.

As a first controlling pulse of electric current, in a winding of themagnetizing coil a pulse can be supplied in form of sets of periodicallymodulated pulses, whose amplitude and/or enveloping line increase from azero magnitude.

As a second controlling pulse of electric current, into the winding ofmagnetizing coil a pulse can be supplied in form of sets of periodicallymodulated pulses, whose amplitude and/or enveloping line reduce to azero magnitude.

In addition, the objective of the invention is solved in that in theknown electromagnet of an electromagnetic drive of an executing driveformed of at least one magnetizing coil on a composite magnetic guidewith an immovable stator, a movable core and at least one air gap,wherein at least a part of the magnetic guide is formed as an insert ofa magnetically hard material with a possibility of controlling amagnetic flux in the magnetic guide by its remagnetization due to asupply of short term current pulses of different polarity into a windingof the magnetizing coil, in accordance with the invention, the magneticguide is formed with the possibility of closing a magnetic flux withminimization of an air gap due to a reciprocating linear displacement ofthe core, wherein the stator is formed as a flat base with at least oneinsert of a magnetically hard material fixed on it, and the core isformed as a steel plate with at least two rods fixed to it with theirends.

The electromagnet is additionally provided with current breakers intothe winding of the coil, formed as normally closed contacts which areconnected in series in a supplycircuit of the winding of the magnetizingcoil and provided with a contact switch with an opening formed in acenter of the base for passing of the contact switch, wherein the coreis provided with a contact pusher which is fixed to the core andprovided with a return spring.

For changing the duration of the current pulse in the winding of themagnetizing coil and turning on and/or turning off of the electromagnet,the current breaker is additionally provided with normally closedcontacts which are connected in series in the supply circuit of thewinding of the magnetizing coil, while the contact switch is formed as apusher with an upper end fixedly connected with the coil, wherein anopening for the contact switch is provided in the center of the base.

The object of the invention is also solved in that the core is formed asa

-shaped plate in a longitudinal cross-section, with side rods connectedwith their ends to the plate, wherein a stator is formed as a rodprovided with an insert of a magnetically hard material.

The object is solved also in that the magnetic guide is formed as twoplates, at least two rods, and at least one insert of a magneticallyhard material, wherein the core is formed

-shaped in a longitudinal cross-section as one plate and two rods,connected to it with their ends, while a stator is formed as a secondplate with at least one insert of a magnetically hard material connectedto it.

The objective of the invention is also solved in that the magnetic guideis formed as two plates, with one insert of a magnetically hard materialconnected to one of the plates, and at least three rods connected withtheir upper ends to the second free plate to form a core with a

-shape in a longitudinal cross-section with a possibility of closing ofthe magnetic circuit with minimization of the air gap.

The objective is solved also in that the core is formed

-shaped in the longitudinal cross-section, wherein at least twomagnetizing coils are located preferably at the end rods of the corewith the possibility of generating of coordinated magnetic fluxes in thecentral rod.

The objective is also solved in that the magnetic guide is additionallyprovided with magnetizing coils located on all rods of the core, and thewinding of one of them is connected opposite to the other windings ofmagnetizing coils.

The objective is also solved in that the magnetic guide is additionallyprovided with a magnetizing coil located on the central rod, whosewinding is connected opposite to the windings of the magnetizing coilslocated on the end rods.

Moreover, the objective of the invention is also solved in that in theknown electromagnet of an electromagnetic guide of an executing deviceformed as at least one magnetizing coil on a composite magnetic drivewith an immovable stator, a movable coil and at least one air gap,wherein at least a part of the magnetic guide is formed as an insert ofa magnetically hard material with a possibility of controlling amagnetic flux in a magnetic guide by its remagnetization due to supplyof short-term current pulses of different polarities into the winding ofthe magnetizing coil, in accordance with the present invention themagnetic guide is formed with the possibility of closing of the magneticflux with minimization of the air gap due to a reciprocatingdisplacement of the core along an arc, preferably a circle, and it has ahousing formed as a disc, with at least one magnetic system located onit, in form of a segment, preferably circular in which a passage-slot isformed with a coaxially located along an arc of a circle, a magnetizingwinding is located in the housing, and the core is located in thepassage-slot and formed as a rod provided with a top and a reversespring and formed with a shape of the slot with a possibility of areciprocating displacement along the arc of the circle in it, whereinthe insert of the magnetically hard material is located on a bottom ofthe passage-slot and fixed to its wall which is orthogonal to thedirection of the displacement of the core and limits its displacement.

Moreover, the objective of the invention is solved in that in the abovementioned known electromagnet of electromagnetic drive of an executingdevice formed as at least one magnetizing coil on a composite magneticguide with an immovable stator, a movable core and at least one air gap,wherein at least one part of the magnetic guide is formed as an insertof a magnetically hard material with a possibility of controlling amagnetic flux in the magnetic guide by a remagnetization of the magneticguide due to the supply of two short term current pulses of equalpolarities into the windings of the magnetizing coil, in accordance withthe present invention the magnetic guide is formed with minimization ofan air gap due to a reciprocating linear displacement of the corerelative to the stator, the stator is formed as a hollow cup, preferablya cylindrical cup, which is provided with at least one rod, at leastpart of which is composed of a magnetically hard material and which isfixed with its one end to a bottom of the cup, while its another end isformed in one plane with an end of the cylinder, wherein at least one ofthe magnetizing coils surrounds the rod, and the core is located outsideof the cup and formed as a plate with a possibility of closing of amagnetic circuit with minimization of an air gap due to the displacementof the core relative to the stator.

As the movable stator, structural elements of metal scrap or load can beutilized.

The objective of the invention is also solved in that in the knownelectric magnet of an electromagnetic drive of an executing deviceformed as at least one magnetizing coil on a composite magnetic guidewith an immovable stator, a movable core, and at least one air gap,wherein at least a part of the magnetic guide is formed as an insert ofa magnetically hard material with a possibility of controlling amagnetic flux in the magnetic guide by remagnetization of the magneticguide due to supply of short term current pulses of different polaritiesinto the magnetizing coil, in accordance with the present invention themagnetic guide is formed with a possibility of closing a magnetic fluxwith minimization of the air gap due to a rotatable displacement of thecore relative to the stator, wherein the stator of the magnetic guide isformed as a cup provided with at least one rod, whose part is composedof a magnetically hard material and which with its one end is connectedto a bottom of the cup, while its another end is formed in one planewith an end of the cylinder, wherein at least one magnetizing coil issurrounded by a rod, the core is located outside of the cup and formedas a plate with a possibility of closing the cup with a cover, and avolume-closed magnetically conductive construction of “cup-cover” isformed with the possibility of changing a moment of a friction forcebetween the core and the stator.

The objective of the invention is also solved in that in the knownelectromagnet of an electromagnetic drive of an executing device formedas at least one magnetizing coil on a composite magnetic guide with animmovable stator, a movable core, and at least one air gap, wherein atleast a part of the magnetic guide is formed as an insert of amagnetically hard material a the possibility of controlling a magneticflux in the magnetic guide by remagnetization of the magnetic guide dueto supply of short-term current pulses having different polarities intothe winding of the magnetizing coil, in accordance with the presentinvention the magnetic guide is formed with a possibility of closing themagnetic flux with minimization of the air gap due to a reciprocatinglinear and/or rotary displacement of the core relative to the stator,wherein the stator of the magnetic guide is formed as a cup with amagnetizing core located in its cavity and with a bottom formed as aninsert of a magnetically hard material, while the core is formed as acover of the cup connected to an end of a rod coaxially located at theinner cavity of the coil, wherein the magnetic guide is formed with apossibility of closing of the cup with the cover with a simultaneoustouching by the free end of the rod with a bottom of the cup, withformation of a volume-closed magnetically conductive construction“cup-cover-rod-bottom of the cup”.

The objective of the invention is also solved in that the bottom of thecup formed of a magnetically hard material with a layer of amagnetically soft material from an outer side of the cup with apossibility of increasing an area of a cross-section of the bottom ofthe cup perpendicular to the direction of the magnetic guide.

The objective is also solved in that the bottom of the cup at leastpartially is formed as an insert of a magnetically soft material with apossibility of changing a friction force of the core relative to thestator.

Finally, the objective of the invention is solved in that at leastpartially the walls of the cup are formed of a magnetically hardmaterial, and the core is formed with a possibility of a linearreciprocating displacement with the possibility of changing of a momentof a friction force relative to the stator.

This execution of the invention provides an increase of exploitationefficiency due to reduction of energy expenses, due to increase ofreliability because of reduction of failures and increase of servicelife before failure, because of improvement of mass-size parameters, andalso by increase of functionality of the electromagnet, or in otherwords the expansion of its functional possibilities.

BRIEF DESCRIPTION OF THE DRAWINGS

Hereinbelow the claimed group of inventions is illustrated by figures ofthe drawings, in which schematically there are shown:

FIG. 1—an equivalent diagram of a magnetic circuit of a compositemagnetic guide of a claimed electromagnet;

FIG. 2—time diagrams of parameters which characterize processes in theclaimed electromagnet with a composite magnetic guide;

FIG. 3—schematic curves of magnetization and energy expenses formagnetization of magnetically hard materials of composite magnetic guideof the claimed electromagnet, and in particular for alloys UN 13DK24with no. 31, UN 15 DK25BA with no.32, UNDK35T5BA with no. 33, 28 CA250(FeBa) with no. 34, KSP37A (SmCo) with number 35 and NdFeB with no. 36;

FIG. 4—a table of electromagnetic properties of the magnetically hardand magnetically soft materials of the composite magnetic guide;

FIGS. 5-8—an electromagnet with a multi-rod composite magnetic guide anda linear reciprocating displacement of a core, a front view, alongitudinal cross-section (FIGS. 5, 7 and 8) and correspondingly a topview (FIG. 6);

FIGS. 9 and 10—an electromagnet with a composite magnetic guide andreciprocating turning displacement of the core, a front view (alongitudinal cross-section) and correspondingly a top view (a transversecross-section;

FIGS. 11 and 12—an electromagnet with a multi-rod composite magneticdrive and a reciprocating linear and/or reciprocating rotarydisplacement of the core, a front view, and correspondingly a top view;

FIGS. 13-16—an electromagnet with a single rod composite magnetic guideand a reciprocating linear and/or reciprocating rotary displacement ofthe core, a front view, a longitudinal cross-section;

FIGS. 17-21—a schematic illustration of processes which take place in adomain structure of a magnetically hard material;

FIGS. 22-25—are tables of properties of sintered and cast magneticallyhard materials in accordance with a Western European standard and itscorrespondence to a standard accepted in pre-Soviet states, includingUkraine.

An important peculiarity of the claimed group of invention is that forits implementation, the following conditions must be satisfied:

1. An air gap must be minimized, which on one hand means that thedispersion field is minimized, and on the hand means that the magneticcircuit is formed closed, is composed of separate parts of aferromagnetic connected in series with one another with a practicallyminimized total resistance of an equivalent magnetic circuit, so that afull magnetic flux passes through each of the parts of the equivalentmagnetic circuit.

2. A ferromagnetic of the closed magnetic circuit of the claimedelectromagnet in FIGS. 5-16 must be necessarily composed of acombination of a magnetically soft and a magnetically hard material,since the formation of the magnetic circuit of the electromagnet only ofthe magnetically hard material, for example from alloys KSP37A (SmSo) orUNDK15, UNDK18 S, UN13DK24, UN13DK25, UN14DK25, etc significantlyincreases the cost and therefore reduces the efficiency of the claimedinvention.

Moreover in this case it is necessary to spend significantly more energyfor remagnetization of the magnetically hard material of the magneticguide of the electromagnet.

The above mentioned combination of the magnetically soft and themagnetically hard materials in the magnetic circuit of the electromagnetin FIGS. 5-16 must be selected so that on the one hand it is possible toprovide a remagnetization of the magnetically hard insert of themagnetic circuit with a possibility of transfer of the magnetic guideinto one (from several) stable condition due to a “magnetic memory” ofthe magnetic hard material, and on the other hand it is possible toreturn the magnetic guide into the original condition of magnetizationwith minimal energy expenses and without the use of special means. Ineach of these cases the magnetically soft material performs the role ofthe magnetic guide with a relatively high magnetic permeability and arelatively low cost, the “magnetic memory” is provided by the use of themagnetically hard material, since the magnetically hard insertpractically completely accumulates the magnetic energy generated by themagnetizing coil.

4. For effective use of the magnetic energy, a possibility of passing ofthe magnetic flux completely through the magnetically hard insert isprovided, or in other words without leaks through parallel branches ofthe magnetic circuit of a magnetically soft material, especially throughair gaps, since otherwise the possibility of realization of the claimedmethod can not be provided. In this case the area of transversecross-section of the magnetically hard insert must have a magnitudewhich is comparable, and in an optimal case which is equal to the areaof the transverse cross-section of the magnetically soft part of themagnetic guide, and their volumes (their masses) must be calculateddepending on the concretely given attracting and holding forces.

5. It is necessary that the direction of vector of intensity of themagnetic field in the magnetically hard material practically coincidewith the direction of location of the domains of a material of themagnetically hard insert, or in other words is necessary to satisfy thecondition cos α=1, wherein α=0 is an angle between the above mentioneddirections;

6. Used magnetically hard materials for a composite magnetic guide(alloys, sintered magnets, etc.) must have, if possible, a minimalenergy which is necessary for their remagnetization (see curves 31-35 inFIG. 3).

7. Supply of controlling magnetizing electromagnet pulse must end withminimization of an air gap, or in other words for satisfying a conditionof maintaining a maximum magnetic energy which is applied to themagnetically hard material.

Satisfaction of the said conditions 1-7 is necessary for providing aremagnetization of the magnetically hard insert during the realizationof the inventive method. Therefore, it is also necessary for astructural implementation of the invention in the claimed devices, whichrealize the claimed method.

In accordance with the invention the realization of these conditions isprovided together with the realization of the claimed method forcontrolling of a magnetic flux in a composite magnetic guide of theelectromagnet by means of:

-   -   transformation of an opened composite magnetic guide into a        ring-shaped closed magnetic guide with a minimal air gap during        its magnetization;    -   and also by its reverse transformation into an open magnetic        guide with a significant air gap during its demagnetization, or        in other words during “zeroing” of the magnetic flux in the        magnetic guide.

When these conditions are satisfied, the ringing of the magnetic fluxover the ferromagnetic of the magnetic guide of the claimedelectromagnet is provided, and MMF which is induced by the winding ofthe magnetizing coil is applied to the ferromagnetic of the magneticguide of the claimed electromagnet between the magnetically soft part ofthe composite magnetic guide and a magnetically hard insert which isconnected with it in series into the magnetic circuit. Thisredistribution is directly proportional to the magnetic resistances ofthese parts of the composite magnetic guide, or in other words inverselyproportionally to their magnetic permeabilities (see equivalent diagramon FIG. 1) since through each of these parts, connected in series withone another in the composite magnetic guide, the same magnetic flux φpasses. Since the magnetic permeability of the magnetically hard insertwhich is a part of the composite magnetic guide is significantly lowerthan the magnetic permeability of the magnetically soft part of the samecomposite magnetic guide, practically the whole MMF (or in any case itsgreater part) is applied to the magnetically hard insert, or in otherwords the intensity of the magnetic field in a magnetically hard insertwill be significant, and its magnitude will be determined practicallycompletely by the magnitude of MMF generated by the winding of themagnetizing coil. This provides a significant value of magnetization ofthe material of the magnetically hard insert which is determined by thevalue B_(work.nom) of the magnetic induction on the curve ofmagnetization in FIG. 2 for the material of the magnetically hardinsert. This value B_(work.mon) of the magnetic induction provides aholding force of the electromagnet, since F is proportional to a productB_(work.nom)×S×m×cos α, wherein

-   B_(work.nom)—a nominal value of working induction;-   S—an area of a transverse cross-section of the magnetically hard    insert;-   M—a mass of the insert;-   α—an angle between a direction of a vector of intensity of the    magnetic field generated by a magnetizing coil and a direction of    orderly location of domains of the material of the magnetically hard    insert. When these directions coincide, then α=0 and cos α=1.

In this case with consideration of the satisfaction of the abovementioned conditions 1-7, the composite closed magnetic guide of theelectromagnet operates as a permanent magnet which is magnetizedpractically to a maximum value of the magnetic induction, or in otherwords to a value which is close to a saturation of a magnetically hardmaterial. In these conditions, it is preferable to form the insert ofthe magnetically hard material, for example from alloy “Alnico” or inother words an alloy of aluminum(Al), nickel (Ni) and cobalt (Co), andin particular from any of many variants of the alloy which aresufficiently widespread and sufficiently inexpensive, wherein the mostsuitable for the realization of the invention are alloys with a lowestenergy for their remagnization, for example the alloy UN13DK24, which isludicated in FIG. 3 with number 31 and is characterized by a value ofthe magnetic induction which is close to the magnetiude of the inductionof saturation B_(max), and correspondingly provides an attractive forceF which several times exceeds the force of a permanent magnet composedof the same materials with the same sizes as the insert in the compositemagnetic guide. In other words, for the cases of the use of the samemagnetically hard material as the insert in the close circuit of themagnetic guide, the magnetic induction will be significantly higher thanin the opened magnetic circuit, and in particularP _(work.nom) :B _(max)=10÷15

For example the magnetically hard insert with a diameter 6 mm and height3 mm from alloy UN13DK24 in the closed magnetic circuit provides theholding force 2.8 kg, and as a permanent magnet less than 200 g.

The insert with a diameter 12 mm and height 8 mm provides the holdingforce in the closed magnetic circuit 15 kg, and as a permanent magnetless than 1 kg.

The composite magnetic guide of the claimed electromagnet (FIGS. 5-16)is composed of a movable 1 and an immovable 2 part and formed with apossibility of closing a magnetic circuit with minimization of the airgap. In this case the immovable part 2 (FIGS. 5-6), which is a stator ofthe magnetic guide, is formed as a flat base with four insert 3 mountedon it and composed of magnetically hard material KSP37A(SmCo) andmagnetizing coils 4, and also a normally closed contacts 5 and 6connected in series in the power supply circuit of the magnetizing coilwith an opening 7 formed in the center of the bottom 2 for passing apusher 8 of switching off of the contacts. The movable part 1 which is acore of the magnetic guide is formed as a steel (steel St3) plate withrods 9 mounted on it (steel St3), formed with a possibility of areciprocating displacement along the axes of the rods. The electromagnetis provided with two return springs 10 and 11, and is closed from a topwith a plug 12. An additional technical result obtained from the use ofthe claimed device shown in FIGS. 5-6 resides in a possibility ofrealization of the invention in actuating devices of a rod type, i.e. indevices whose drives can be located between magnetizing coils, i.e.coaxially with the electromagnet system. These can be actuating devicesin magnetic starters, contractors, vacuum switches, closing devices forblocking of locks of save boxes, automobiles, doors, etc. constructionswhich prevent an unauthorized penetration, and also in locking valves,etc. When compared with known constructions of an electromagnet theclaimed invention provides the possibility of operation in a pulse modewithout consumption of energy by the windings 4 of the magnetizing coilsin stable conditions, with the exception of moments of switching. As aresult, finally there is a possibility to considerably (by one order andmore) increase current intensity in the windings 4 of the coils and anumber of amper-convolutions of the magnetizing coil and correspondinglyto increase pulling and holding forces of the electromagnet with asimultaneous reduction of its mass-size characteristics.

Explanations of pecularities of variants of carrying out of theconstruction of the claimed electromagnet and pecularities of theclaimed method realized in these constructions are presented below.These pecularities of carrying out of the invention are their concreteillustrations and do not present any limitations for the invention as awhole.

In the electromagnet of the electromagnet drive in FIG. 7, the coil 1 isformed as a steel plate (steel 10) which is π-shaped in a longitudinalcross-section, wherein the rods 9 are formed from the plate 1 of thecore, and the stator 2 is formed as a bar and provided with an insert 3of a magnetically hard material, which is also formed as a bar of alloyKSP37A (SmCo) mounted on the stator. The additional technical resultobtained from the use of the claimed device shown in FIG. 7 resides inexpansion by means of its use, for example, in magnetic starters, whichprovides an optimal setting of the apparatus.

In the electromagnet of the electromagnetic drive shown in FIG. 8 themagnetic guide is formed as two plates 1 and 2 of a magnetically softmaterial (St 3). A magnetically hard insert 3 (alloy UNDK15) is fixed tothe plate 2 (stator) and is located in an axial passage of themagnetizing coil 4. The core 1 is formed as a steel (steel 10) plate andthree rods fixed with their ends to a plate 1 which is

-like in a longitudinal cross-section. The rods 9 have a length toprovide closing of the magnetic flux in a magnetic guide withminimization of the air gap with a reciprocal linear displacement of thecore. The additional technical result obtained from the use of theclaimed invention shown in FIG. 8 also resides in expansion offunctional possibilities of the claimed electromagnet by means of itsuse, for example in contactors, etc., with providing an optimal settingof the electromagnet system with a minimal metal consumption.

With the electromagnet of an electromagnetic drive shown in FIGS. 9 and10, the magnetic guide is formed with a possibility of closing themagnetic circuit with minimization of the air gap due to a reciprocatingdisplacement of the core along an arc of the circle 1, and it contains asteel (St3) housing 10 formed as a disc, with two horse shoe-shapedmagnetic systems located on it and formed as circular segments 11. Eachsegment has a passage-slot 12 with coaxial side walls 13 and 14extending along an arc of a circle. The windings of the magnetizingcoils 4 are located in the housing 10. The coil 1 formed as a rod with atop 15 and a return spring 16 is located in the passage-slot 12 andformed in correspondence with the shape of the slot with a possibilityof reciprocating displacement in it along the arc of the circle. Theinsert 3 of magnetically hard material-alloy KSP37A (SmCo) is located onthe bottom of the passage-slot 12 and fixed to its wall 17, which isorthogonal to the direction of displacement of the core 1 and limits itsdisplacement. In addition to the windings of the magnetizing coils 4,windings of demagnetizing coils 18 are located in the housing 10 andprovide a supply of controlling pulse of opposite polarity. Theadditional technical result provided from the use of the claimed deviceshown in FIGS. 9 and 10 resides in expansion of functional possibilitiesof the claimed electromagnet by means of its use for example inoverrunning and ratchet couplings due to creation and use of additionalfunctions of these couplings and in particular turning on, turning off,changing of directions of rotation, angular displacement with a givenstep. Also, this is achieved by its use in valves of hydraulic systemswith a possibility of regulation of a cross-section of a passage.

In the electromagnet of the electromagnetic drive shown in FIGS. 11 and12 the magnetic guide is formed with the possibility of closing of themagnetic flux with minimization of an air gap due to reciprocatinglinear displacement of the core relative to the stator formed as a steelcup 19 which is turned upside down (steel St3). The stator is providedwith five rods 9 (steel St3), which are partially composed of amagnetically hard material-alloy KSP37A (SmCo) in form of insets 3connected to the bottom 20 of the cup 19. Each rod 9 is connected to theinsert 3 and forms its extension so that the outer end surfaces of therods 9 are located in the same plane with the end surface of the cup 19.Each of the rods 9 is surrounded by a magnetizing coil 4, while themovable core 1 is formed as a disc with the possibility of closing ofthe magnetic circuit of the magnetic drive with its surface during thereciprocating linear and/or rotary displacement of the core 1 relativeto the stator 9. This variant of carrying out of the electromagnet ischaracterized in that, as the movable core 1 it is possible to usestructural elements of metal scrap and/or load, and because of this theclaimed electromagnet can be used as an economical method oftransportation of scrap and other metallic loads. When the electromagnetis formed with a possibility of reciprocating linear and/orsimultaneously rotary displacement of the core relative to the stator,the claimed construction can be used as a coupling for torquetransmission, as a braking mechanism and for other similar purposes.Thereby the functional possibilities of the claimed electromagnet areexpanded even more. In the claimed variant of the electromagnet themagnetizing coils are connected so that they create coordinated addingmagnetic fluxes in the magnetic guide. In the analyzed variant ofcarrying out of the claimed electromagnet, the winding of the coil 4arranged on the middle of the rod 9 can be connected with thepossibility of creating an opposite magnetic flux and using it fordemagnetization. An additional technical result of this variant of theclaimed electromagnet resides in a possibility of changing a moment of afriction force between the core and the stator.

In the electromagnet of the electromagnetic drive shown in FIG. 13, themagnetic drive is formed with the possibility of closing of the magneticflux with minimization of an air gap due to a reciprocating linearand/or rotary displacement of the core relative to the stator. In thiscase the stator is formed as a (steel St3) cup 21, with a bottom 3composed of a magnetically hard material—alloy KSP37A (SmCo) and pressedagainst an end surface of the cup 21 by a screw cap 26 composed of a nonmagnetic material. The magnetizing coil 4 is coaxially located in theinner cavity 22 of the cup 21 and the core is formed as a cover of thecup 23 connected to the steel (steel St3) rod 9 which is coaxiallylocated in the inner cavity 24 of a casing 25 of the magnetizing coil25. The magnetic guide is formed with the possibility of closing of thecup 21 with the cover 23 with the simultaneous touching of the thee endof the rod 9 with the bottom 3 of the cup 21 and formation of avolume-closed construction “cup 21-cover23-rod 9-bottom 3 of the cup 21”and a magnetization of the bottom 3 of a magnetically hard material withproviding a holding force of the electromagnet which is practicallyequal to a pulling force generated by the magnetizing winding 4 with thepossibility of changing a moment of a friction force between the coreand the stator. The additional technical result of this variant of theclaimed electromagnet shown in FIG. 13 resides in an increase of alength of stroke, since the rod of the core is located inside the cupalong its whole length and also an increase of reliability due toincrease of interference protection of the magnetic system frominfluences of external magnetic fields.

In the electromagnet of the electromagnetic drive shown in FIG. 13, thebottom 3 of the cup 21 is formed of a magnetically hard materialprovided from the outer side with a magnetically soft layer 27, whichallows to increase the holding force of the electromagnet due to theincrease of the area of the magnetically hard material whichparticipates in a remagnetization and “memorization” of the magneticflux.

In the electromagnet of the electromagnetic drive shown in FIG. 14, thebutton 3 of the cup 21 is composed of a magnetically hard material, andits surface from the side of the core is formed with an insulation inform of a layer 27 of a magnetically soft material. This allows toimpart to the core a rotary movement without a risk that due to thefriction between the core and the stator, irreversible processes in adomain structure of the magnetically hard material of the bottom 3 ofthe cup 21 can occur.

In the electromagnet of the electromagnetic drive shown in FIG. 16, thestator, in form of the hollow steel cup 21, which at least partially iscomposed of a magnetically hard material in form of a ring 28, a bottom3 of the cup 21 is composed of a magnetically soft material and ispressed by a screw cap 26 of a non-magnetic material against the endsurface of the cup 21.

The additional technical result obtained from the use of the variant ofthe claimed device shown in FIG. 16 resides in a possibility ofproviding a linear reciprocating displacement and change of a moment offriction force between the core and the stator.

It is analytically determined and confirmed practically that theincrease of the number of the rods of the rod core of the claimedelectromagnet allows to increase the area of transverse cross-section ofeach of them, since for the claimed construction (see for example FIGS.5-16) a total area of their transverse cross-section is important. Onthe other hand, the series connection of the magnetizing coils of theserods allows to reduce a total quantity of amper-convolutions provided bythese windings, i.e. to maintain (and even increase) MMF and anattracting force provided by the electromagnet with a simultaneousreduction of copper consumption, since structurally a significantreduction of an average length of the convolution I_(av) of the windingis provided, which creates the necessary amper-convolutions. Thereforein the electromagnet with a movable rod core, which use four cups, anadditional effect is provided in the economy of a copper consumptionapproximately two times.

Moreover, an additional effect of the claimed group of inventions isdetermined analytically and confirmed experimentally, in that the pulsepower supply of the windings of the magnetizing coils of the claimedelectromagnet, independently from the above mentioned effect, allows toreduce copper consumption 3÷5 times more (depending on the structuralpecularities) due to the increase of the electrical power of thecontrolling pulse. This is connected with the fact that the short timeof the pulse action on the winding of the electromagnet and the absenceof electrical current in the winding before the supply of the secondcontrolling pulse, in accordance with the present invention, providesuch a thermal mode of exploitation of the electromagnet, that thewindings of the magnetizing coils are not heated. Thereby, aspractically determined, both additional effects together provide areduction of metal consumption by 50-90%.

The use in the claimed method and in the claimed electromagnet of ademagnetizing current pulse allows to use as the magnetically softmaterial of a composite magnetic guide, any magnetically conductivesteel, including conventional structural steel, instead of the specialelectrotechnical steel, without the risk that the movable core willadhere. In addition, the pulse control of the electromagnet provides areduction of losses in steel (eddy currents, losses for remagnetization,etc.) which allows to get rid of a composite, or in other wordsparticulate, core of the electromagnet. This reduces the cost, which isan additional technical effect provided by the claimed invention.

The absence of current in the magnetizing coil of the electromagnet intwo basic conditions of the magnetic guide provides the absence ofnoises and vibrations when compared with the magnetic conditions ofcontactors (starters, etc), whose windings in a working condition areunder voltage, which represents also an additional technical result.This leads to an increase of exploitation reliability due to reductionof “low mechanical wear” of contacts and parts of the electrical drive,which as a result increases the efficiency of the claimed group ofinventions.

The supply to the magnetizing winding of the claimed electromagnet ofshort term controlling current pulses allows, with comparible pullingcharacteristics and holding forces of the electromagnet, to reducesignificantly the metal consumption of the claimed electromagnet and toincrease the current intensity of the controlling pulse. This is anotheradditional technical result provided by the claimed invention andresiding in significant reduction of mass-size characteristics.

The reduction of the mass of the movable parts of the electromagnet andsimultaneously a significant reduction of possibility of riveting inplaces of mechanical contact of the metallic parts also contributes tothe increase of efficiency. Also, the effect of pneumatic dampening ofthe rods of the core in internal cavities of the magnetizing coil, whichis an additional technical result from the use of the claimed group ofinventions, contributes to it.

An additional technical result from the use of the claimed invention isthat in the case of the use of the invention in contactors, switches andetc. devices, the pecularity of the claimed invention lead to the factthat first of all a force of compression of the contacts of thecontactors does not depend on reduction of supply voltage, and secondlythe increase of supply voltage can not lead to a heating of the windingof the magnetizing coil of the contactor, since in a working conditionit is currentless and does not use electrical energy.

A qualitative-quantitative analysis is presented herein below, whichmust be considered as an example of realization of the claimed method,and also of the claimed electromagnet. From this analysis thepeculiarities of the claimed method of controlling of the magnetic fluxin the composite magnetic guide of the claimed electromagnet andpeculiarities of the construction of the claimed electromagnet becomeeven more clear.

For analysis of the magnetic circuit, it is convenient and accepted touse analogy between magnetic and electrical circuits. In this case themagnetic circuits usually can be presented as electrical diagrams whichrepresent flowing of electrical current in a circuit that iselectrically analogous to the analyzed magnetic circuit. Herein belowthose analogous electrical circuits are analyzed. The electrical circuitshown in FIG. 1 represents an equivalent closed magnetic circuit of thecomposite magnetic guide of the claimed electromagnet. In this case themagnetic guide, at least partially is composed of a magnetical hardmaterial. An analysis of this circuit is given herein below, presentedas elements connected in series. A part of a magnetic guide (on the diagam of FIG. 1) composed of a magnetically hard material is shown as asource of a magnetically moving force (MMF) and a magnetic resistanceR_(T) of a magnetic material, while a part composed of a magneticallysoft material is shown as a magnetic resistance R_(M). Correspondinglyan air gap of a composite magnetic guide is shown in FIG. 1 as amagnetic resistance R₃. For simplification the analysis is made with anassumption that a dispersion of the magnetic flux, eddy currents, andother non-important phenomena for explanations are conditionallyconsidered within the magnetic resistance R₃ of the air gap. Then themagnitude of the magnetically moving force MMF of the analyzed circuitis proportional to the residual magnetization of the magnetic guide ofthe material, and magnitudes of magnetic resistances R_(T), R_(M), R₃,of correspondingy magnetically hard material, magnetically soft materialand air gap are proportional to magnetic permeabilities correspondingμ_(T) of magnetically hard material, μ_(M) of magnetically softmaterial, and μ3 of the air gap. In addition, they are correspondinglyproportional to the duration (length) of the power flux lines of themagnetically hard material, magnetically soft material, and magnitude ofair gap. It is clear that with increase of duration (magnitude) of airgap, the magnetic resistance R₃ of this air gap will increase in asquare ratio, and vice versa with reduction of duration (magnitude) ofthe air gap, the magnetic resistance R₃ of this gap will reduce incorrespondence with this ratio.

FIG. 2 shows time diagrams of the parameters that characterize thephysical processes which take place in a composite magnetic guide of theclaimed electromagnet, which is at least partially composed of amagnetically hard material, during the realization of the claimed methodof controlling the magnetic flux of the electromagnet. On the diagram I(t) a time dependence of the controlling pulses of electric current inthe winding of the magnetizing coil is presented, or in other wordsdependence of the magnitude of electric current from time. Analogously,on diagram H(t) a time dependence of voltage of magnetic field is shown.On the diagram view μ_(T)(t) a time dependency of the magneticpermeability in the magnetically hard material is shown. On the diagramμ_(m)(t) a time dependency of the magnetic permeability of themagnetically soft material is presented. On the diagram R_(M) (t) a timedependency of the magnetic resistance of the magnetically hard materialis presented. On the diagram R₃(t) a time dependency of the magneticresistance of the magnetically soft material is presented. On thediagram R₃(t) a time dependency of the magnetic resistance of the airgap is presented. On the diagram R_(E)(t) a time dependency of a totalmagnetic resistance of the composite magnetic guide is presented. On thediagram MMF(t) a time dependency of the magnetic moving force acting inthe magnetic guide is presented. On the diagram φ(t) a time dependencyof the magnetic flux in the magnetic guide is presented. On the diagramB_(T)(t) a time dependency of the magnetic induction in the magneticallyhard material is presented. On the diagram B_(M)(t) a time dependency ofthe magnetic induction in the magnetically soft material is presented.On the diagram F(t) a time dependency of a force of the electromagnetwhich attracts the core is presented. On the diaphragm δ(t) a timedependency of the magnitude of the air gap is presented.

From the time point t₁ an increase of voltage H of the magnetic field toa value determined by an amplitude of the controlling pulse of theelectric current I in the winding of the magnetizing coil starts. Inaccordance with the increase of voltage H of the magnetic field from thetime t₁ an increase of magnetic permeability μ_(T) of magnetically hardmaterial starts from the value μ₀ to the value μ_(max) and subsequentits reduction to the minimal magnitude μ_(min) caused by saturation ofthe magnetically hard material. Analogous changes take place for themagnetic permeability μ_(M) in the magnetically soft material. In thisprocess the magnetic permeability μ_(M) of the magnetically softmaterial which does not have a clearly expressed saturation, increasesto the valuewhich is 1.5-2 times greater than the magnetic permeabilityμ_(T) of the magnetically hard material, which is a clearly expressedsaturation (see FIG. 2 and Table 1). The changes in time of the magneticresistance R_(T) of the magnetically hard material and the magneticresistance R_(M) of the magnetically soft material which represent thesevalues are inversely proportional to the corresponding magneticpermeabilities and shown on the time diagrams R_(T)(t) and R_(M)(t)correspondingly. As can be seen from the time diagrams R_(T)(t) andR_(M)(t), the said magnetic resistances in a moment of time to t1 startreduce, and this reduction continues until the current values R_(T)(t)and R_(M)(t) reach the values determined by a magnitude of maximummagnetic permeability μ_(max), wherein the magnetic resistance of themagnetically soft material assumes its final value which 1.5-2 timeslower than the magnetic resistance of the magnetically hard material. Atotalmagnetic resistance R_(E) of the composite magnetic guide at leastpartially composed of a magnetically hard material (see FIG. 1) can bepresented as a sum of the magnetic resistances of the magnetically hardmaterial R_(T) a magnetically soft material R_(M), and an air gap R₃. Itshould be mentioned that the value of the magnetic resistance of thevalue R₃ of the air gap is a function which is proportional to square ofthe magnitude of the air gap δ and which starts reducing in the momentof time t1, while in the moment of time t₂ it reaches its minimal value.In the same time moment, the magnitude of the magnetic resistance of theair gap R₃ reaches its minimal value.

The magnitudes of magnetic inductions B_(T) in the magnetically hard andB_(M) in the magnetically soft materials and the magnitude of themagnetic flux φ in the magnetic guide, and also the value of themagnetic moving force MMF in the moment of time t1 start increasing dueto increase of voltage of the magnetic force H and reduction of a totalmagnetic resistance of the magnetic guide R_(E) and ends its increaseafter the end of increase of voltage of the magnetic field H, and of theprocess of magnetization of the magnetically hard and magnetically softmaterial and of the process of minimization of the air gap. Theattracting force F1 which is a function of the magnetic flux and isinversely proportional to square magnitude of air gap also startsincreasing at the moment of time t1 and reaches at maximum value itsreaching by the value of air gap δ of its minimal value.

The above mentioned physical magnitudes maintain their values to themoment of time t3, i.e. to the moment of end of action of thecontrolling pulse of the electric current in the winding of themagnetizing coil. In this time moment t3 the voltage H of the magneticfield and the magnetic force MMF start reducing. However, this reductionis limited by a preserved magnetization of the magnetically hardmaterial, and the magnitude of magnetization of the magnetically hardmaterial in turn is limited by a low total magnetic resistance R_(E) ofthe magnetic guide, which is maintained due to high voltage H of themagnetic field. Thereby a fact which is practically found by, that andwas not known before, takes place, namely a presence of a positivefeedback between the above mentioned magnitudes and in particularbetween H, B_(T), B_(M), μ_(T), μ_(M), R_(T) and R_(M). These magnitudesmutually prevent reduction of each other.

Thus, with reduction of voltage of the magnetic field H (see FIG. 2) theresidual magnetic induction (magnetizatin) of the magnetical hardmaterial generates a magnetically moving force MMF whose magnitude isthe greater, the greater B_(T). In the closed magnetic circuit B_(T) ofthe magnetic guide (see for example FIG. 1) the magnetically movingforce MMF generates a magnetic flux φ, whose value isφ=MMF/R _(E)  (1)wherein R_(E) is a total magnetic resistance of the equivalent magneticcircuit on FIG. 1.

At the same timeR _(E) =R _(T) +R _(M) +R ₃  (2)

-   wherein R_(T)—a magnetic resistance of the magnetically hard    material of the magnetic guide-   R_(M)—a magnetic is a magnetic resistance of a magnetically soft    material of the magnetic guide;-   R₃—a magnetic resistance of the air gap.

As a result of this, the magnetic flux φ determines the magnetization ofthe magnetically soft material. A result of the above mentionedphenomena is that the magnetic permeabilities of the magnetically hardmaterial μ_(T) and of the magnetically soft material μ_(M)correspondingly of the magnetic guide remain practically the same as inthe interval of time from t1 to t2 in FIG. 2. Therefore the magneticresistances R_(T) of the magnetically hard material and correspondinglyR_(M) of the magnetically soft materially practically do not changetheir magnitudes during the remagnetization, i.e. during magnetizationand demangetization. Since the value of the air gap δ remains minimal(minimized), the magnetic resistance R₃ of the air gap and a totalmagnetic resistance R_(E) of the equivalent closed circuit on themagnetic drive in FIG. 1 retain their values at the level which is closeto the values that took place in the interval of time from t1 to t2 inFIG. 2. This new property of the composite magnetic circuits that wasdiscovered by the inventor of this invention have a great importance forthe claimed group of invetions—the claimed method of controlling amagnetic flux in a composite magnetic guide of the electromagnet and theclaimed construction of the electromagnet in which this method is used,since it determines a so-called “effect of lock” or effect which isanalogous to a “trigger effect”. As a result of the above mentionedprocesses, the voltage of the magnetic fuel H, a magnitude of themagnetic induction B_(T) in the magnetically hard and B_(M) in themagnetically soft material, the magnetical moving force MMF, themagnetic flux φ and the attracting force F of the electromagnet maintaintheir values at the level of 80-98% of the values, which these variableshad in the moment of time t₃. The described condition is only one ofstable conditions of the magnetic guide. This stable condition ismaintained till supply of a second controlling pulse into themagnetizing windings at the moment of time t₄.

In the examined case the second controlling pulse must have an opposite(when compared with the first controlling pulse) polarity and itsmagnitude I must provide voltage H of the magnetic field, which is equalto coercitive force Hc of the magnetically hard material (see diagramH(t). On time diagrams this condition corresponds to the time moment t5.In this time moment a complete demagnetization of the magnetically hardmaterial takes place, i.e. a current value B_(T) reaches a valueB_(T)=0, while a magnetic permeabilities μ_(T) of the magnetically hardand μ_(M) of the magnetically soft materials, magnetic resistance R_(T)of magnetically hard and R_(M) of the magnetically soft materials, R₃ ofair gap and a total magnetic resistance R_(E) of the magnetic guide,magnetic inductions B_(T) of the magnetically hard and B_(M) of themagnetically soft materials, magnetic flux φ, attracting force F and themagnitude of an air gap δ are subjected to changes which have a natureopposite to the changes described within the time interval from t1 tot2, without consideration of remagnetization of the ferromagneticmaterials of the magnetic guide, i.e. without consideration ofpeculiarities of remagnetization of the magnetically soft material ofthe core and the magnetically hard material of the insert. The currentvalue of the magnetic flux φ=0 and described values of other parameterscharacterize a second stable condition of the electromagnet.

On the time diagram I(t) shows the beginning of the action in the momentof time t7 of the second controlling current pulse in a winding of themagnetizing coils is shown, providing one more, third, stabile conditionof the magnetic guide which is analogous to the stable conditiondescribed in the interval from t3 to t4 with a difference that a vectorof the magnetic flux φ has a direction which is opposite to thedirection described in the interval of time from t3 to t4. For obtainingof this (third) stabile condition, it is necessary to supply in thewinding of the magnetizing coil a controlling pulse whose polarity isopposite to the polarity that takes place in the interval of time fromt1 to t2, with an amplitude which is sufficient for remagnetization ofthe magnetically hard material, or in other words with an amplitudewhich is greater than H_(T) (see FIG. 2, time diagram H (t) in theinterval of time from t4 to t6). Time dependencies of the parametersshown in FIG. 2 in the interval of time from t3 to t4 will be the sameas in the interval of time from t1 to t2, with the difference that thevoltage of the magnetic field H, the magnetic flux φ, the magneticinductions B_(T) of the magnetically hard and B_(M) of the magneticallysoft materials will have an opposite polarity.

The claimed electromagnet (FIGS. 5-16) operates in the following manner.

When voltage is supplied to the winding 4 of the magnetizing coil and amagnetic flux φ in the composite magnetic guide of the electromagneticis excited, an attraction of the movable core 1 of the magnetic systemto the immovable stator 2 takes place, regarding of the polarity of thesupplied controlling voltage. This magnetic flux provides attraction ofthe core 1 of the magnetic system to the stator 2 with overcoming of aforce generated by the return spring 10 and therefore minimizes the airgap δ of the magnetic guide of the electromagnet. After closing of themagnetic circuit, the magnetic flux φ in the closed magnetic guide isringed. After removing the voltage from the winding 4 of the magnetizingcoil, the magnetic flux φ accumulated in the magnetically hard insertcontinues to hold the domains oriented along the magnetic power fluxlines. The maximum holding force depends on an initial pulse of thewinding 4 and a volume of the material of the magnetically hard insert3. After mechanical interruption of the magnetic circuit, the domains ofboundary layers of the magnetically hard insert 3 are partiallyreoriented, which corresponds to a residual magnetization of thematerial of the magnetically hard insert. Due to this, the magnitude ofthe holding force F of the electromagnet reduces approximately by oneorder. A complete “zeroing” of the magnetic flux in the material of themagnetically hard insert 3 corresponds to the case of an approximatelyequal, i.e. approximately equally, subdivision of the domains with amutually cancelling magnetic fluxes in the magnetic guide of the claimedelectromagnet. The magnetically hard insert 3 from alloy Alniko afterthe magnetization in the composite closed guide becomes with its holdingforce by one order more powerful than the same insert which ismagnetized outside of the closed magnetic circuit.

The magnetic flux in the composite magnetic guide provides aminimization of air gap δ in the magnetic guide, i.e. minimization ofthe magnitude of equivalent magnetic resistance of the compositemagnetic guide, and a subsequent remagnetization of the magneticallyhard material of the composite magnetic guide, and this remagnetizationprovides “memorization” of the magnetic flux in the currentlesscondition of the winding 4 of the magnetizing coil. This “memorization”of the magnetic flux can be explained in that, the magnetically hardinsert 3 is a monocrystal or a pseudo monocrystal in the case of ananizothropic material with a hexagonal structure, which is automaticallysubdivided into domains, in which the magnetic flux is completely closedwithin the simplest sample (FIGS. 17-21), while outside of it themagnetic force at the end surfaces of the elements of the magnetic guidepractically completely disappears. Near the surface of the same betweenthe domains, border layers of a finite thickness are created. In theirvolume, in accordance with a certain low, a turning of the vector ofmagnetization I_(s) occurs from its orientation in one domain to itsorientation in another domain. For the formation of the border layer, acertain “border” or surface energy is spent, whose magnitude issignificantly smaller than the volume energy disappearing during theformation of the ringing field of the sample. Thereby, the formation ofdomain structure is in effect of self-closing of the ferromagneticbodies at the voltage H out=0. The presence with H out=0 of a residualmagnetization I_(R) in the samples (in the case of permanent magnets)can be explained by an influence of interval defects and the structureof the crystal, which make difficult the process of closing, i.e. duringthis process an incomplete compensation of the resulting magnetic momentof the whole sample is obtained and the presence of the dispersion fieldin the places of exit of the layers. Monocrystals which have aplane-parallel domain structure (see FIG. 19) are composed ofalternating areas, whose directions of magnetization are anti-parallel.In these cases and in addition to the main domains A, B, C, D . . .there are so-called closing a, b, c, d domains of a border layer.

If a “demagnetized” ferromagnetic layer with a domain structure isplaced into outer magnetic field, it is “magnetized”, i.e. the domainswith the direction of magnetization which is closer to the direction ofvoltage of the external magnetic field with grow due to “eating up” ofthe volume of their less efficiently magnetized neighbors. This processis performed due to a displacement of border layers between the domains.Simultaneously with this, a turning of the vector I_(S) of magnetizationwill occur with respect to a direction of the outer magnetic field-aprocess of rotation. A natural displacement of the borders of thedomains and rotation of the vector of magnetization in them determine atype of dependency of the resulting magnetization of ferromagneticsamples and their magnetic induction from the outer magnetic field,determine a shape of a magnetization curve.

If a sample of a magnetically hard material is placed in a volume-closedmagnetic circuit of the magnetic guide, formed of a magnetically softmaterial, then after the action by the outer magnetic field, the borderlayers of the sample are opened, oppositely directed domains of thesample are reoriented in correspondence with the outer magnetic field,and a simple domain structure shown in FIGS. 17, 18 is modeled. In otherwords, in this case the magnetically hard insert is fixed in conditionwith open border layers of domains and reoriented main domains, and thefunctions of the closing domains after interruption of pulse currentsupply into the winding of the magnetizing coil are transferred to partsof the core and the stator, located perpendicular to the direction ofthe outer magnetic flux—see FIGS. 20 and 21.

The claimed constructions allow to combine positive qualities of themagnetically soft material, whose magnetization curve is characterizedby a higher magnetic sensibility (permeability) which determinesincrease of magnetization (induction) in weak fields, has a very narrowhoop of hysteresis, an insignificantly small coercitive force, greatresidual magnetization close to the magnetization of saturation, withadvantages of the magnetically hard material which is a stabile sourceof a strong field with a maximum broad (close to a rectangular) loop ofhysteresis, i.e. with a high coercitive force and residualmagnetization, close to the magnetization of saturation.

MMF in the magnetically soft and magnetically hard materials are added.

After the mechanical breaking of the magnetic circuit of the compositemagnetic guide on end surfaces of the magnetic guide demagnetizationpoles are created, and the insert 3 is returned to the conditioncorresponding to the residual magnetization, i.e. the ferromagneticmaterial becomes a bipolar permanent magnet, i.e. the magnetically hardinsert transfers from the condition with maximum magnetization (borderlayers open) to the condition of residual magnetization (border layersclosed), whose magnitude is lower by one order.

The return of the core 1 to an initial position is provided by ashort-term current pulse into an oppositely wound winding, or by a pulsevoltage of an opposite polarity with a calculated amplitude, or acalculated duration of current, or by a set of extinguishing pulseoscillations, or by action of a return spring.

The author confirmed by calculations and experiments a significantefficiency of the claimed group of inventions, which is provided bothbecause of energy savings, and also on account of a significantreduction of accidental failures and increase of a service life withoutfailure of commutating devices, i.e. due to increased work beforefailure, as well as due to significant expansion of functionalpossibilities of the use of the claimed variants of the construction ofthe electromagnet.

The claimed invention provides the following technical result during itsuse:

-   Claimed electromagnet operates both in circuits of alternating    current and direct current;-   Claimed electromagnet provides at least two stable    energy-independent conditions of the magnetic guide;-   Magnetic guide of claimed electromagnet can be composed of a    non-alloyed steel;.-   Claimed electromagnet provides a significant (by one order) increase    of a pulling force or significant reduction of area of transverse    cross-section and significant reduction of mass-size parameters, as    well as a reduction of metal consumption of copper 3÷5 times and    magnetically soft metal (steel)7-10 times.-   Reduction of inertia and increase of response time of the    electromagnet;-   Reduction of riveting of elements of the magnetic guide and increase    of their resistance;-   Increase of service life of executing contacts of a commutation    electrical equipment;-   Increase of a holding force of claimed electromagnet with a    magnetically hard insert of the composite magnetic guide, for    example of alloy UN13DK24, which more than 3 times increases the    holding force provided by a permanent magnet in the case of open    non-composite magnetic guide of the same size composed of alloy of    rare-earth metal, neodymium (Nd), iron (Fe), and boron (B). In    accordance with the data of the author, this result could be reached    with a previous solutions only with a deep cooling of the    magnetically hard material;-   Significant expansion of functional possibilities of the claimed    construction, including due to the possibility of its use in    commutation electrical equipment, in electromagnetic couplings for    transmission of torques, in braking mechanisms and similar    constructions.

The above mentioned advantages of the claimed invention when comparedwith the known technical solutions, their features and properties arepresented in generalized form in table 2 wherein the followingindicators are used: Analog 1 technical solution from a German patentapplication DE 196 39545; Analog 2 technical solution from Europeanpatent EP 074540; Analog III technical solution from internationalapplication PCT/UA00/0005.

The analysis of the data of the table 2 and the above mentioned dataconfirms the correspondence of the claimed group of inventions tocriteria of protection, and in particular to criteria of “novelty”“inventive level” and “industrial utility”.

In addition, the claimed group of inventions satisfy the principle ofunity of the invention, since one of the objects of the claimed group,and in particular a construction of the electromagnet, is provided forthe use of the other object, in particular a method of controllingmagnetic flux in the magnetic guide of the electromagnet.

Sources of information taken into consideration.

-   1. DE No. 19639545 A1 of Dec. 18, 1997, ICON, AG PRAZISIONSTECINIC    (1);-   2. EP 0794540 A1 of Sep. 10, 1997 HARTING KGaA CNJK, TW 2 CNIJRB    prototype (2).-   3. DE No. 19639545 A1 of Dec. 18, 1997 ICON, AG PRAZISIONSTECINIC    (3);-   4. EP 0794540 A1 of Sep. 10, 1997 HARTING KGaA CNJK, TW 2 CNIJRB    prototype (4).-   5. PCTUA00/0005 HO1F 7/16, 7/124, EO5B 47/02, Feb. 03, 2000    BABICH, N. S.-prototype (5).-   6. GOST 17809-72 Magnetically Hard Cast Materials, M, Gosstandart,    1986, p. 4-5;

7. A. D. Smirnov, K. M. Antipov, Guide Book for Energy Expert, M.,Energoatomizdat, 1987, p. 254. TABLE 2 Important features and Claimedproperties solution Analog 1 Analog 2 Analog 3  1. Minimization of airgap + − − +  2. Presence of closed + − − + magnetic circuit  3. Presenceof composite + − + + magnetic guide  4. Absence of parallel + − − +branches (areas) of magnetic circuit, so that magnetic flux completelyis transmitted through magnetically hard insert  5. α = 0 and cosα = 1 +− − +  6. Use of magnetically + − − + hard materials with minimal energyfor remagntetization  7. Retaining “magnetic + − − + memory”.  8.Ability to operate in + + + + circuits of alternating and directcurrent.  9. Present at least two + − − + stable energy independentconditions of magnetic guide of electromagnet 10. Possibility to make +− − + magnetic guide from inexpensive easy-to- machine non-alloyed steelof the type ST3, ST10, ST20, etc.

1. Method of controlling a magnetic flux of an electromagnet with arelay pulling characteristic, determined by stable levels of values of amagnetic flux in a composite magnetic guide, which at least partially iscomposed of a magnetically hard material, by supplying control pulses ofelectric current into a winding of a magnetizing coil with a possibilityof obtaining a holding force of a movable part of the magnetic guide,with at least one air gap, characterized in that the magnetically hardmaterial is used which has an ability to maintain during aremagnetization at least two stable conditions of magnetization, and ascontrolling pulses of electric current two short duration pulses ofopposite polarity are supplied into the winding of magnetization of thecomposite magnetic guide, wherein during the supply of the first pulse,closing of the magnetic circuit of the magnetic guide is provided andminimization of a magnetic resistance of the magnetic guide due tominimization of air gap of the magnetic guide with a subsequentmaximization of the magnetic flux in the magnetic guide and its transferinto one of stable conditions, characterized by a maximum value of themagnetic flux in the magnetic guide which corresponds to energy ofcontrolling pulse action, with a possibility of staying of the compositemagnetic guide of the electromagnet in the stable condition andproviding a holding force til a supply of another controlling pulse ofelectric current of an opposite polarity whose energy characteristic inmagnitude is sufficient for transfer of the magnetic guide into anotherstable condition which is characterized by another magnitude of themagnetic flux which corresponds to it, and another magnitude of theholding force which corresponds to it.
 2. Method according to claim 1,characterized in that the supply of the first controlling current pulseinto the winding of the magnetizing coil with a subsequent maximizationof the magnetic flux in the composite magnetic guide is performed afterthe minimization of the air gap.
 3. Method according to claim 1,characterized in that the supply of the first controlling current pulseinto the winding of the magnetizing coil with a subsequent maximizationof the magnetic flux in the composite magnetic guide is performed beforeminimization of the air gap.
 4. Method according to claim 1,characterized in that the magnitude of the controlling magnetic flux inthe composite magnetic guide of the electromagnet due to the firstcontrolling pulse of electrocurrent in the winding of the magnetizingcoil of the electromagnet before closing of the magnetic circuit of themagnetic guide is performed at a level of its optimal value which isnecessary for generating a working pulling force of the electromagnetand it is maintained at this level until a magnetization of the materialof the magnetic guide, and thereafter the electrical pulse voltage isremoved from the winding of the magnetizing coil, while the holdingforce of the electromagnet is provided due to a “magnetic memory” of thematerial of the composite magnetic guide with the possibility ofobtaining a holding force whose magnitude is F≦0.98 F_(max), whereF_(max) is a maximum value of the magnetic force generated by thewinding of the magnetizing coil.
 5. Method according to claim 1,characterized in that the necessary power of the controlling pulses witha possibility of providing the required holding force of theelectromagnet is provided due to change of parameters of the controllingpulses, selected from a set consisting of an amplitude of a pulse, itsduration, its shape, and their combinations.
 6. Method according toclaim 1, characterized in that into the winding of the magnetizing coila second controlling current pulse is supplied with a different energycharacteristic when compared with a characteristic of the firstcontrolling pulse, and a transition is provided of the magnetization ofthe magnetic guide into another stable condition which is characterizedby a corresponding magnitude of a magnetic flux in the compositemagnetic guide and a corresponding value of the holding force.
 7. Methodaccording to claim 6, characterized in that the transition of themagnetic guide into a stable condition characterized by the magnitude ofthe magnetic flux in the magnetic guide equal to zero is provided, bysupplying into the winding of the magnetizing coil of a controllingcurrent pulse which provides a voltage of the magnetic field in themagnetic guide equal to coercitive force on a magnetizing curve and acorresponding magnitude of holding force.
 8. Method according to claim7, characterized in that one of the stable conditions of the compositemagnetic guide is its initial condition which is characterized by amagnetic force whose magnitude is equal to an initial value and aholding force corresponding to it.
 9. Method according to claim 7,characterized in that the power P₂ of the second controlling pulse ofcurrent of opposite polarity is 2-5 times lower than a power P₁ of thefirst controlling current pulse of a direct polarity and constitutesP₁=(2÷−5)P₂.
 10. Method according to claim 1, characterized in that theduration t1 of the first controlling pulse of electric current of thedirect polarity in the winding of the magnetizing coil andcorrespondingly a magnetic flux in the composite magnetic guide of theelectromagnet of direct polarity and t2 of the second controlling pulseof opposite polarity do not exceed a triple magnitude of a constant oftime τ of a transitional process for a mass of a movable part of themagnetic guide, i.e. t1≦3 τ and t2≦3 τ, wherein τ is a constant of timeof the transition process.
 11. Method according to claim 1,characterized in that as the first controlling current pulse, into thewinding of the magnetizing coil a pulse is supplied in form of a set ofperiodically modulated pulses, whose amplitude and/or enveloping curveincrease from a zero value.
 12. Method according to claim 1,characterized in that as a second current pulse, into the winding ofmagnetizing coil a pulse is supplied in form of a set of periodicallymodulating pulses whose amplitude and/or enveloping curve extinguish toa zero value.
 13. Electromagnet of an electromagnetic drive of anexecuting device formed as at least one winding of magnetization on acomposite magnetic guide with an immovable stator, a movable core and atleast one air gap, wherein at least partially the magnetic guide isformed as an insert of a magnetically hard material with a possibilityof controlling a magnetic flux in the magnetic guide by itsremagnetization due to the supply of short duration current pulses ofdifferent polarity into the winding of magnetizing coil, characterizedin that the magnetic guide is formed with a possibility of closing amagnetic flux with a minimization of the air gap due to reciprocatinglinear displacement of the core, wherein the stator is formed as a flatbase with at least one insert of a magnetically hard material fixed onit, while the core is formed as a steel plate with at least two rodsmounted on it by their ends.
 14. Electromagnet according to claim 13,characterized in that it is additionally provided with a current breakerin the winding of the coil, formed as normally closed contacts which areconnected in series in a circuit of power supply of the winding of themagnetizing coil and provided with a contact switch, wherein an openinglocated in a center of its base for passage of the contact switch,wherein the core is provided with a contact pusher which is fixed to thecore and provided with at least one return spring.
 15. Electromagnetaccording to claim 13, characterized in that the core is formed as aplate with a

-like shape in a longitudinal cross-section, in which side rods arefixed with their ends, while the stator is formed as a bar provided withan insert of a magnetically hard material.
 16. Electromagnet accordingto claim 13, characterized in that the magnetic guide is formed as twoplates, at least two rods, and at least one insert of a magneticallyhard material, wherein the core is formed with a

-like shape with a longitudinal cross-section in form of one plate andtwo rods connected to it with their ends, while the stator is formed asa second plate with an insert composed of a magnetically hard materialand fixed on it.
 17. Electromagnet according to claim 13, characterizedin that the magnetic guide is formed as two plates with at least oneinsert of a magnetically hard material connected to it and at leastthree rods connected by upper ends to a second plate so as to form acore with a

-like shape in a longitudinal cross-section with the possibility ofclosing of the magnetic circuit with minimization of an air gap. 18.Electromagnet according to claim 17, characterized in that the core isformed with a

-like shape in a longitudinal cross-section, wherein at least twomagnetizing coils are located preferably on the rods of the core withthe possibility of creating coordinated magnetic fluxes in the centralrod.
 19. Electromagnet according to claim 18, wherein the magnetic guideis additionally provided with a magnetizing coil located on a centralrod of the core, and its winding is connected in coordination with thewindings of the magnetizing coils located on the end rods. 20.Electromagnet according to claim 19, wherein the winding of one of themagnetizing coils is connected in opposition.
 21. Electromagnet of anelectromagnetic drive of an executing device formed as at least onemagnetizing coil on a composite magnetic guide with a movable stator, animmovable core and at least one air gap, wherein at least partially themagnetic guide is formed as an insert of a magnetically hard materialwith a possibility of controlling a magnetic flux in the magnetic guideby its remagnetization due to supply of short duration current pulseshaving different polarities into the winding of the magnetizing coil,characterized in that the magnetic guide is formed with the possibilityof closing the magnetic flux with minimization of air gap due toreciprocating turning displacement of the core along an arc and includesa housing formed as a disc on which at least one magnetic system isplaced and has a shape of the segment, preferably circular segment, inwhich a passage-slot is provided with coaxially located side wallsarranged in a plane along an arc, preferably a circle, a magnetizingcoil is located in the housing, and the core is located in thepassage-slot and formed as a rod with a top and a return spring whichhas a shape of the slot with the possibility of a reciprocatingdisplacement in it, wherein the insert of a magnetically hard materialis located on the bottom of the passage-slot and fixed to its wallperpendicularly to the direction of displacement of the core andlimiting its displacement.
 22. Electromagnet of an electromagnetic driveof an executingdevice formed as at least one magnetizing coil on acomposite magnetic guide with a movable stator, an immovable core and atleast one air gap, wherein at least partially the magnetic guide isformed as an insert of a magnetically hard material with the possibilityof controlling a magnetic flux in the magnetic guide by remagnetizationof the magnetic guide due to supply of two short duration pulses ofdifferent polarities into the winding of the magnetizing coil,characterized in that the magnetic guide is formed with the possibilityof closing of a magnetic flux with minimization of an air gap due to thereciprocating linear displacement of the core relative to the stator,the stator is formed as a cup provided with at least one rod, whose partis composed of a magnetically hard material, and which has one endconnected to a bottom of the cup and another free end formed in oneplane with an end of a cylinder, wherein at least one of the magnetizingcoils embraces the rod, and a core is located outside of the cup andformed as a plate with the possibility of closing of the magneticcircuit with minimization of the air gap due to the displacement of thecore relative to the stator.
 23. Electromagnet of claim 22,characterized in that as the core, structural elements of metal scrapand/or load are used.
 24. Electromagnet of claim 22, wherein themagnetic guide is formed with the possibility of closing of the magneticflux with minimization of air gap due to rotary displacement of the corerelative to the stator, the core is formed as a plate with thepossibility of closing of the cup with a cover, formation of avolume-closed magnetically conductive construction “cup-cover” and withthe possibility of changing a moment of friction force between the coreand the stator.
 25. Electromagnet of an electromagnetic drive of anexecuting device formed as at least one magnetizing coil of a compositemagnetic guide with a movable stator, a movable core and at least oneair gap, wherein at least partially magnetically guide is composed of aninsert of a magnetically hard material with the possibility ofcontrolling a magnetic flux in the magnetic guide by a remagnetizationof the magnetic guide by supply of two, short duration current pulses ofdifferent polarities into the winding of the magnetizing coil,characterized in that the magnetic guide is formed with the possibilityof closing of the magnetic flux with minimization of air gap due tolinear and/or rotary displacement of the core relative to the stator,wherein the stator of the magnetic guide is formed as a cup with amagnetizing coil coaxially located in its inner cavity, and with abottom composed of a magnetically hard material, while the core isformed as a cover of the cup connected to an end of the rod which iscoaxially located in the inner cavity of the winding, wherein themagnetic guide is formed with a possibility of closing of the cup withthe cover with a simultaneous touching of the free end of the rod withthe bottom of the cup, and formation of a volume-closed magneticallyconductive construction “cup-cover-rod-cup bottom” and a possibility ofchanging a moment of friction force between the core and the stator. 26.Electromagnet of claim 25, characterized in that the cup bottom iscomposed of a magnetically hard material with a layer of a magneticallysoft material and an outer side of the cup with the possibility ofincreasing an area of cross-section of the cup bottom perpendicularly tothe direction of the magnetic flux.
 27. Electromagnet of claim 25,characterized in that the cup bottom is partially formed as an insert ofa magnetically soft material.
 28. Electromagnet of claim 25,characterized in that at least partially the walls of the cup are formedas an insert of a magnetically hard material.